Multiwell agar gel punch

ABSTRACT

A multiwell agar gel punch to be used in screening biological samples which comprises a support for holding microscopic slides containing agar gel, and a hinged top member, which has a multiplicity of resiliently mounted punches, arranged in patterns, which when imparted to the agar gel, makes possible a rapid precipitation between pairs of the wells. When one well is charged with a sample of serum or plasma, and the other well is charged with a specific antibody serum, the slide is then subjected to a conventional, high-voltage immunoelectroosmophoresis.

United States Patent Walter Farris 19193 Parkside, Detroit, Mich. 48221 [21] Appl. No. 41,840

[22] Filed June 1,1970

[45] Patented Jan.4, 1972 Continuation-impart of application Ser. No. 19,035, Mar. 12, 1970, now Patent No. 3,600,772. This application June 1, 1970, Ser. No. 41,840

[72] Inventor [54] MULTIWELL AGAR GEL PUNCH 5 Claims, 6 Drawing Figs.

[52] US. Cl 85/599, 83/691 [51] Int. Cl B261 1/02 [50] Field of Search 25/105; 83/599, 607-609, 691

[56] References Cited UNITED STATES PATENTS 2,230,778 2/1941 Flores 25/105 2,217,560 10/1940 Michon 83/699 X 792,949 6/1905 Dorin 83/599 X 3,384,941 5/1968 Koike et al... 25/105 3,500,710 3/1970 Taber 83/691 X 3,520,220 7/1970 Acker 85/599 X 3,563,124 2/1971 Gargrave 83/691 Primary Examiner-.1 Spencer Overholser Assistant Examiner-B. D. Tobor Attorney-Edward M. Apple ABSTRACT: A multiwell agar gel punch to be used in screening biological samples which comprises a support for holding microscopic slides containing agar gel, and a hinged top member, which has a multiplicity of resiliently mounted punches, arranged in patterns, which when imparted to the agar gel, makes possible a rapid precipitation between pairs of the wells. When one well is charged with a sample of serum or plasma, and the other well is charged with a specific antibody serum, the slide is then subjected to a conventional, high-voltage immunoelectroosmophoresis.

MULTIWELL AGAR GEL PUNCH This application is a continuation-in-part of my copending application, Ser. No. 19,035, filed March 12, I970 now U.S. Pat. No. 3,600,772.

This invention relates to agar gel punches used in medical research, and in particular to a multiple-well agar gel punch for screening biological samples, wherein the punches are arranged in a predetermined pattern or patterns, so that a rapid precipitation may be effected between pairs of the wells when subjected to a conventional, high-voltage immunoelectroosmophoresic process.

An object of the invention is to provide a device which makes possible the rapid screening of blood samples, to determine the presence or not of hepatitis or other antigens in the blood, to be used in a transfusion.

Another object of the invention is to provide a device of the character indicated which will enable an immunoelectroosmophoresic test to be made on a blood sample in as little time as 2 hours.

Another object of the invention is to generally improve agar gel punches and to provide a multiwell punch which is efficient in operation, economical to manufacture, and sufficient in use.

Another object of the invention is to provide a device of the character indicated in which a multiplicity of gel punches are resiliently mounted in a cover member, and are arranged for easy installation and replacement.

Another object of the invention is to provide a punch capable of forming a multiplicity of wells in the. agar gel of a microscopic slide, which wells are arranged and spaced in such a manner as to facilitate the rapid and positive precipitation between pairs of the wells when subjected to a conventional immunoelectroosmophoresic action.

Another object of the invention is to provide a base for supporting a microscopic slide and an eccentrically mounted top member, which carries a plurality of punches; the top and base being arranged to be parallel at all times, in order to compensate for microscopic slides of different thickness, and to limit the pressure exerted by the punches on the slides.

Another object of the invention is to provide a device of the character indicated with means to limit the movement of the punch-carrying top, relative to the base, when the parts are in parallel relation.

The foregoing and other objects of the invention will become more apparent as the description proceeds, reference being made from time to time to the accompanying drawing, forming part of the within disclosure, to which drawing:

FIG. 1 is a perspective view of a device embodying the invention showing a microscopic slide in position on the base, and showing the punch-carrying top member pivoted upwardly, and out of working position.

FIG. 2 is a top plan view of the device shown in FIG. I, with the top down and with parts broken away, to illustrate the relation of other parts.

FIG. 3 is a fragmentary, side, elevational view of the device shown in FIGS. 1 and 2.

FIG. 4 is a section taken substantially on the line 4-4 of FIG. 3.

FIG. 5 is an enlarged, fragmentary section taken substantially on the line 5-5 of FIG. 4.

FIG. 6 is a modified form of the top member, in which the gel punches are arranged in a different pattern to that shown in FIG. 1.

Referring now more particularly to the drawing, it will be understood, that in the embodiment herein disclosed, the reference character 7 indicates the base of the device, and the reference character 8 indicates the top.

The base 7 is preferably formed as an aluminum casting with vertical risers 9, on which is supported the microscopic glass slide 10, the top of which is treated with agar gel 10A (FIG. 5), in which it is proposed to form a multiplicity of wells by means of the punches 11, which are mounted in the top 8, as hereinafter described. The top 8 is pivoted to the base 7 as at 12. The pivot 12 is an eccentric mounting between the base 7 and the top 8, as more fully described in my copending application, so that the base 7 and the top 8 may always be parallel to one another, when the punches 11 are brought in contact with the microscopic slide 10.

In order to regulate the amount of pressure exerted by the punches 11 on the slide, I provide a spring-backed limit pin 13, similar to the one described in my copending application. The pin 13 reciprocates in a fitting 14, at the top of which is a circular handgrip 15, which is used to raise and lower the top member 8. The top member 8 consists of a pair of rectangular plates 16 and 17, which are held together by means of machine screws 18 (FIG. 3). The plates 16 and I7 are supported on the underside of a hinge strap 19 by means of machine screws 20, or other suitable means. The hinge strap 19 thus becomes an integrated part of the top 8.

As shown in FIG. 4, it will be seen that the plate 17 is provided with a plurality of vertical bores 21, in which are slidably mounted the punches 11. The punches 11 are tubular in form, (as shown in FIG. 5) and have tapered cutting edges 11A, the easier to penetrate the agar gel 10A. The upper ends of the punches 11 are flared, as at 22, which flares prevent the punches 11 from being displaced from the plate 17. The plate 16 (FIGS. 4 and 5) has a plurality of transverse slots 23 formed on its underside, in each of which slot is positioned a soft resilient element 24, such as rubber or other material. Each resilient element 24 overlies a row of the punches 11, and serves to provide a resilient backingfor the punches.

It will be understood that the punches 11 (FIG. 1) are arranged in six rows, or three pairs of rows. The punches of each pair of rows are from 1.0 to L6 centimeters from center to center. The diameter of each punch is from 3 to 4 millimeters, although other dimensions may be employed, all of which is within the contemplation of the invention.

It will be understood, therefore, that when the plurality of punches is brought into contact with the microscopic slide 10, there will be formed in the agar gel 10A, a plurality of wells equal to the number of punches 11, which wells will be in paired rows, as previously described. After the paired rows of wells are formed in the agar gel 10A, the slide 10 is removed from the base, and the agar gel is permitted to firm up, after which the wells are charged with the blood samples and with the test antibody serum.

It will be understood that one well is paired with its adjacent well in the same pair of rows, when the slide is then placed in the immunoelectroosmophoresic equipment (not shown). When the high-voltage current is passed through the agar gel, and there is a presence of serum hepatitis antigens in the serum or plasma sample, a positive precipitation will develop between the two wells, to indicate a positive reaction in the test.

Although I have briefly indicated the reaction in the immunoelectroosmophoresic operation, it will be understood that such operation constitutes no part of the invention, as my invention resides in the multiple-well gel punch itself.

Although I have herein described the preferred pattern of the punches and wells, it will be understood that I intend to modify the pattern (as shown in FIG. 6), in which a plurality of punches are positioned and equally spaced around a central punch. This would be particularly useful in testing by simple diffusion.

It is believed that the operation of the device is obvious from the foregoing description.

Having described my invention, what I claim and desire to secure by Letters Patent is:

l. A multiwell agar gel punch comprising the combination of a base member having an upper area for receiving thereon an agar gel microscopic slide, means to hold the slide against lateral displacement, a top member eccentrically pivoted to said base, said top member consisting of a pair of matched plates, means to secure said plates to one another, a hinge strap secured to the upper plates of said pair and to an extension of said base member, the lower one of said plates having rows of apertures therein, a gel punch slidable in each aperand punches in an adjacent row.

4. The structure of claim 1, in which the apertures and punches of each row are arranged in groups, the aperture and punches of each group being spaced approximately L0 to 1.6 centimeters from center to center.

5. The structure of claim 1, in which the punches are tubular and each punch has an inside diameter of from 3 to 4 millimeters.

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1. A multiwell agar gel punch comprising the combination of a base member having an upper area for receiving thereon an agar gel microscopic slide, means to hold the slide against lateral displacement, a top member eccentrically pivoted to said base, said top member consisting of a pair of matched plates, means to secure said plates to one another, a hinge strap secured to the upper plates of said pair and to an extension of said base member, the lower one of said plates having rows of apertures therein, a gel punch slidable in each aperture, the upper one of said plates having a longitudinal recess therein above, each row of apertures in said lower plate, and a resilient element in each said recess in contact with a row of said punches.
 2. The structure of claim 1, in which said punches are flared at their upper ends to prevent displacement from said apertures, and said resilient elements overlie the flared ends of said punches.
 3. The structure of claim 1, in which the apertures and punches in each row are equally spaced from the apertures and punches in an adjacent row.
 4. The structure of claim 1, in which the apertures and punches of each row are arranged in groups, the aperatures and punches of each group being spaced approximately 1.0 to 1.6 centimeters from center to center.
 5. The structure of claim 1, in which the punches are tubular and each punch has an inside diameter of from 3 to 4 millimeters. 